/Engine/Plugins/Runtime/MeshModelingToolset/Source/MeshModelingTools/Public/EditMeshPolygonsTool.h
Extrude the current set of selected faces. Click in viewport to confirm extrude height.
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(CallInEditor, Category=TriangleEdits, Meta=(DisplayName="Extrude", DisplayPriority=1)) void Extrude()